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2016 MERCEDES-BENZ C450

Owner reports · Recalls · Investigations

Limited comparison data

There is not enough comparable history to draw a useful model-year comparison.

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Counts vary with age, sales and reporting. They are not failure rates.

What owners reported most

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When problems were reported

Mileage at the reported incident

Limited mileage data: 8 of 16 reports include usable mileage. There isn’t enough coverage to show a useful chart.

NHTSA’s mileage field refers to the reported incident, not necessarily the filing date. This shows report counts, not the likelihood of a failure.

What to inspect

Issues worth paying extra attention to based on owner reports.

  • Wheels. Review the 5 owner reports in this category and discuss these concerns during a pre-purchase inspection. Read reports →
  • Electrical System. Review the 4 owner reports in this category and discuss these concerns during a pre-purchase inspection. Read reports →
  • Structure. Review the 4 owner reports in this category and discuss these concerns during a pre-purchase inspection. Read reports →

NHTSA owner reports · September 18, 2026 snapshot.

0 crash reports0 fire reports0 injury reports

What owners actually said

16 reports
51,000 miles · Mar 10, 2020
Structure

AS PER THIS RECALL LISTED 2016 MERCEDES-BENZ C300, C450 AMG 4MATIC RECALLED FOR PANORAMIC SUNROOF DEFECT. I BOUGHT THIS CAR AS A CERTIFIED USED MODEL FROM A MERCEDES DEALERSHIP AND WHILE DRIVING THE PANORAMIC SUNROOF ATTEMPTED TO STAND UP VERTICALLY BUT I QUICKLY CAUGHT IT. I PULLED OVER AND MANAGED TO GET IT TO CLOSE AND LAT…

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AS PER THIS RECALL LISTED 2016 MERCEDES-BENZ C300, C450 AMG 4MATIC RECALLED FOR PANORAMIC SUNROOF DEFECT. I BOUGHT THIS CAR AS A CERTIFIED USED MODEL FROM A MERCEDES DEALERSHIP AND WHILE DRIVING THE PANORAMIC SUNROOF ATTEMPTED TO STAND UP VERTICALLY BUT I QUICKLY CAUGHT IT. I PULLED OVER AND MANAGED TO GET IT TO CLOSE AND LATCH AND TOOK IT TO THE DEALER NAMED IN THE REPAIR ESTIMATE. I PROVIDED THEM WITH THE PLASTIC PIECES SHOWN IN THE PICTURE THAT I FOUND BROKEN INSIDE THE FRAME AND THEY WOULD NOT REMEDY THE DEFECT WITHOUT A CHARGE OF OVER $3200 WHICH INCLUDED PARTS THAT ARE NOT MALFUNCTIONING. INSTEAD I WAS SENT BACK OUT WITH THE VEHICLE IN THE SAME CONDITION

NHTSA ODI #11317270

39,000 miles · Oct 24, 2019
Wheels

DEFECTIVE 19'' MERCEDES-BENZ AMG ALLOY RIM CRACKED AND CAUSED TIRE PRESSURE FAILURE.

NHTSA ODI #11270791

46,000 miles · Feb 1, 2019
Wheels

SINCE I BOUGHT THE MY 2016 C450 AMG IN 2016 BRAND NEW I STARTED HAVING ISSUES WITH THE RIMS A MONTH LATER AFTER PURCHASING THE CAR. I TOOK IT BACK TO THE SERVICE DEPARTMENT AND THEY TOLD ME IT WAS A CRACKED RIM ,I RESPONDED BY LETTING THEM KNOW I NEVER RAN OVER ANY POTHOLES.THE RIM WAS REPAIRED, BUT A MONTH LATER AGAIN THE PROBL…

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SINCE I BOUGHT THE MY 2016 C450 AMG IN 2016 BRAND NEW I STARTED HAVING ISSUES WITH THE RIMS A MONTH LATER AFTER PURCHASING THE CAR. I TOOK IT BACK TO THE SERVICE DEPARTMENT AND THEY TOLD ME IT WAS A CRACKED RIM ,I RESPONDED BY LETTING THEM KNOW I NEVER RAN OVER ANY POTHOLES.THE RIM WAS REPAIRED, BUT A MONTH LATER AGAIN THE PROBLEM ACCURRED.MY CAR HAS BEEN IN THE SERVICE DEPARTMENT FOR THE SAME PROBLEM EVERY OTHER MONTH FOR THE SAME PROBLEM ON EACH OF MY TIRES ,ALL OF MY TIRES HAVE BEEN CRACKED WITHOUT ME RUNNING INTO POTHOLES.JUST YESTERDAY I RECEIVED MY CAR BACK FROM SERVICE AFTER A WEEK OF THEM HAVING IT FOR A CRACKED RIM AGAIN ON THE FRONT RIGHT SIDE.WHEN I LEFT THE SERVICE DEPARTMENT THE TIRE PRESSURE WAS AT 36 PERCENT THIS MORNING ALL THE TIRES ARE AT THEIR NORMAL PRESSURE EXCEPT THE RIGHT FRONT TIRE IT'S AT 30 PERCENT. IT IS LOSING AIR AGAIN. MY CAR HAS BEEN TO THE SERVICE DEPARTMENT OVER 15 TIME FOR PROBLEMS WITH CRACK RIMS WITHOUT ME RUNNING INTO POTHOLES. IS THERE A MANUFACTURING PROBLEM WITH THE RIMS?

NHTSA ODI #11173497

25,070 miles · Jan 7, 2019
Electrical SystemSteering

WHILE DRIVING DOWN THE 405 FREEWAY VEHICLE LOST POWER STEERING ASSIST AT 65MPH, VEHICLE STEERING WAS VERY HARD TO STEER & STEERING WHEEL LIGHT ILLUMINATED ON THE DASH HAD TO FIGHT WITH THE STEERING TO PULL THE VEHICLE OFF TO THE SIDE OF THE FREEWAY. TRY TO RESTART VEHICLE ALL LIGHT CAME ON NO-START. BATTERY CABLE HAD TO BE REMOV…

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WHILE DRIVING DOWN THE 405 FREEWAY VEHICLE LOST POWER STEERING ASSIST AT 65MPH, VEHICLE STEERING WAS VERY HARD TO STEER & STEERING WHEEL LIGHT ILLUMINATED ON THE DASH HAD TO FIGHT WITH THE STEERING TO PULL THE VEHICLE OFF TO THE SIDE OF THE FREEWAY. TRY TO RESTART VEHICLE ALL LIGHT CAME ON NO-START. BATTERY CABLE HAD TO BE REMOVED WAIT 30MIN AND VEHICLE RESTARTED. TOOK THE VEHICLE TO THE DEALER IN BEVERLY HILLS, DEALER DIAGNOSIS AND FOUND SOME DTC'S CODES AND RESET AND RETURN VEHICLE

NHTSA ODI #11164987

24,000 miles · Mar 13, 2018
Wheels

TL* THE CONTACT OWNS A 2016 MERCEDES-BENZ C450. THE CONTACT NOTICED THAT THE FRONT AND REAR PASSENGER TIRES WERE DEFLATING. THE VEHICLE WAS TAKEN TO MERCEDES-BENZ OF CHERRY HILL (2151 NJ-70, CHERRY HILL, NJ 08002) WHERE IT WAS DIAGNOSED THAT THE RIMS WERE CRACKED DUE TO DRIVING OVER POTHOLES. THE VEHICLE WAS NOT REPAIRED. THE M…

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TL* THE CONTACT OWNS A 2016 MERCEDES-BENZ C450. THE CONTACT NOTICED THAT THE FRONT AND REAR PASSENGER TIRES WERE DEFLATING. THE VEHICLE WAS TAKEN TO MERCEDES-BENZ OF CHERRY HILL (2151 NJ-70, CHERRY HILL, NJ 08002) WHERE IT WAS DIAGNOSED THAT THE RIMS WERE CRACKED DUE TO DRIVING OVER POTHOLES. THE VEHICLE WAS NOT REPAIRED. THE MANUFACTURER WAS NOT NOTIFIED OF THE FAILURE. THE APPROXIMATE FAILURE MILEAGE WAS 24,000.

NHTSA ODI #11078936

3,000 miles · Jun 10, 2016
Unknown Or OtherWheels

SINCE THE PURCHASE OF OUR 2016 MERCEDES IN DECEMBER OF 2015, WE HAVE BEEN EXPERIENCING THE WARNING DISPLAY OF THE TIRE PRESSURE ON NUMEROUS OCCASIONS. THE FIRST OCCURRENCE PRIOR TO TAKING IT TO A DEALERSHIP MY WIFE TOOK IT A LOCAL TIRE SHOP WHERE THE OWNER PUT AIR IN THE TIRES AND THE LIGHT WENT OFF. IT OCCURRED SEVERAL MORE T…

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SINCE THE PURCHASE OF OUR 2016 MERCEDES IN DECEMBER OF 2015, WE HAVE BEEN EXPERIENCING THE WARNING DISPLAY OF THE TIRE PRESSURE ON NUMEROUS OCCASIONS. THE FIRST OCCURRENCE PRIOR TO TAKING IT TO A DEALERSHIP MY WIFE TOOK IT A LOCAL TIRE SHOP WHERE THE OWNER PUT AIR IN THE TIRES AND THE LIGHT WENT OFF. IT OCCURRED SEVERAL MORE TIMES AND I ALWAYS WENT TO LOCAL GAS STATIONS AND PUT AIR IN. AFTER GETTING FRUSTRATED WE DROVE TO THE DEALERSHIP IN VALENCIA CALIFORNIA SHOWED THE SERVICE ATTENDANT THE ALERT ON THE DASH. HE RETRIEVED AN AIR PUMP AND PUT AIR IN ALL THE TIRES ACCORDING TO THE SPECS AND SENT US ON OUR WAY WITHOUT DISCUSSING THE WARNING ALERT WHICH WENT OFF. AFTER APPX A WEEK AND A HALF OF DRIVING WE RETURNED WITH THE SAME PROBLEM.. MY WIFE SPENT 4 HOURS WAITING AND ACCORDING TO THE SERVICE RECEIPT THEY SAID THE TIRES WERE ROTATED AT THE CLIENT'S REQUEST AND NEVER MENTIONED THE ALERT ON THE DASH BEING REPORTED BY THE OWNER. WE HAVE TAKEN IT A COUPLE OF MORE TIMES ONE OF WHICH THE CHECKED AND SUBMERGED ALL THE TIRES TO CHECK FOR LEAKS AND RIM DAMAGE WHICH THEY ALL CHECK OUT PROBLEM FREE. AND AS USUAL THE ALERT CAME BACK ON AFTER APPX. A WEEK AND A HALF OF DRIVING. TODAY THE ALERT IS BACK ON WITH ANOTHER RED WARNING SIGN AND WE ARE GOING TO DRIVE IT BACK TO THE DEALERSHIP IN VALENCIA TOMORROW SINCE THEY WILL NOT SEND A TOW SERVICE OUT WHEN THE OWNER'S MANUAL CLEARLY STATES "IN DANGER OF AN ACCIDENT PULL OVER AND DO NOT DRIVE". THIS IS THE SECOND RED LIGHT WARNING ON THE VEHICLE AND IT APPEARS THEY HAVE NO IDEA WHAT THE PROBLEM IS. ON THE FIRST OCCASION WHEN THE RED LIGHT CAME ON WE WERE INSTRUCTED TO DRIVE THE VEHICLE IN REGARDLESS OF THE RED LIGHT WARNING. I CONTACTED THE MERCEDES BENZ USA COMPLAINT DEPARTMENT THIS MORNING AND FILED A COMPLAINT. THE DEPT OF CONSUMER AFFAIRS INSTRUCTED ME TO FOLLOW THE ARBITRATION GUIDELINES IN THE BACK OF THE MANUAL.

NHTSA ODI #10873656

Official recalls

5

23V854000 · Structure:body:roof And Pillars

Dec 15, 2023

Mercedes-Benz USA, LLC (MBUSA) is recalling certain 2014-2020 C-Class, CLA, GLA, S-Class, GLC, and GLE vehicles. Please refer to MBUSA's recall report for specific vehicle details. The front roof panel located between the windshield and the panoramic sunroof may not have been bonded correctly to the vehicle during a prior repair, allowing the front panel to detach from the vehicle.

Consequence & remedy

Consequence: A detached roof panel can become a road hazard, increasing the risk of a crash.

Remedy: Dealers will replace the front panel, free of charge. Owner notification letters were mailed on August 2, 2024. Owner notification letters will be mailed in phases, on, March 22,2024, and August 2, 2024. Owners may contact MBUSA customer service at 1-800-367-6372. This recall is an expansion of NHTSA recall number 21V-197.

21V197000 · Structure:body:roof And Pillars

Mar 19, 2021

Mercedes-Benz USA, LLC (MBUSA) is recalling certain 2017-2020 C300 Coupe, C43 Coupe AMG, C43 AMG, 2015-2020 C300, GLA250, 2016-2018 C350e, CLA45 Coupe AMG, 2015 C400, S65 AMG, 2015-2019 C63 AMG, 2016 C450, 2015-2016 GLA45 AMG, S600, 2016-2020 GLC300, 2017-2019 GLC43 AMG, GLE43 Coupe AMG, 2014-2019 CLA250 Coupe, 2014-2015 CLA45 AMG, 2018 GLC63 AMG, 2014-2017 S550, 2018-2020 S450, 2016-2019 GLE63 Coupe AMG, 2016 GLE450 Coupe, 2014-2020 S63 AMG, 2018-2019 S560, and 2019 GLC350e vehicles equipped with a panoramic sunroof. The front roof panel located between the windshield and the panoramic sunroof may not have been bonded correctly to the vehicle during a prior repair.

Consequence & remedy

Consequence: The adhesive bonding of the front panel might deteriorate, possibly causing the front panel to detach from the vehicle and become a road hazard, increasing the risk of a crash.

Remedy: Mercedes-Benz dealer will remove the bonded panel and will install a new front panel by following the detailed repair instructions and using the approved primer, cleaner and adhesive, free of charge. Owner notification letters were mailed on September 3, 2021 and October 26, 2021. Owners may contact MBUSA customer service at 1-800-367-6372.

19V787000 · Communication

Nov 1, 2019

Mercedes-Benz USA, LLC. (MBUSA) is recalling certain 2013-2017 vehicles due to a software fault that may cause the date and time for the emergency call system (eCall) to differ from the actual date and time, potentially relaying an inaccurate vehicle location. For a full list of the affected models visit: https://static.nhtsa.gov/odi/rcl/2019/RMISC-19V787-4620.pdf

Consequence & remedy

Consequence: An inaccurate vehicle location may delay emergency responders, increasing the risk of injury.

Remedy: MBUSA has initiated an Over the Air (OTA) remote update. MBUSA will also notify owners, and dealers will check software for a successful OTA or update the communication module software as needed, free of charge. The recall began December 23, 2019. Owners may contact MBUSA customer service at 1-800-367-6372. MBUSA's number for this recall is 2019120008.

17V114000 · Electrical System:starter Assembly; Engine And Engine Cooling:engine

Feb 23, 2017

Mercedes-Benz USA, LLC. (MBUSA) is recalling certain 2015-2017 C300 4Matic, C300, CLA250, CLA250 4Matic and CLA45 AMG vehicles, 2017 C300 4Matic Cabrio, C300 4Matic Coupe, C300 Cabrio, C300 Coupe, E300, E300 4Matic, E400 4Matic Wagon, E43 AMG 4Matic, GLA250, GLA250 4Matic and GLC300 4Matic Coupe vehicles and 2016 C350e and GLC300 vehicles and 2016-2017 C450 4Matic AMG Sport and GLC300 4Matic vehicles. In the event that the engine or transmission cannot turn over, the starting current limiter may overheat from the repeated attempts of the starter motor attempting to start the vehicle.

Consequence & remedy

Consequence: If the starting current limiter overheats, the surrounding components can melt, increasing the risk of a fire.

Remedy: MBUSA will notify owners, and dealers will install an additional fuse in the electrical line to the starter, free of charge. The recall began August 31, 2017. Owners may contact MBUSA customer service at 1-800-367-6372. MBUSA's number for this recall is 2017080002.

Additional source detail variants (2)

Electrical System:starter Assembly

Mercedes-Benz USA, LLC. (MBUSA) is recalling certain 2015-2017 C300 4Matic, C300, CLA250, CLA250 4Matic and CLA45 AMG vehicles, 2017 C300 4Matic Cabrio, C300 4Matic Coupe, C300 Cabrio, C300 Coupe, E300, E300 4Matic, E400 4Matic Wagon, E43 AMG 4Matic, GLA250, GLA250 4Matic and GLC300 4Matic Coupe vehicles and 2016 C350e and GLC300 vehicles and 2016-2017 C450 4Matic AMG Sport and GLC300 4Matic vehicles. In the event that the engine or transmission cannot turn over, the starting current limiter may overheat from the repeated attempts of the starter motor attempting to start the vehicle.

Consequence: If the starting current limiter overheats, the surrounding components can melt, increasing the risk of a fire.

Remedy: MBUSA will notify owners, and dealers will install an additional fuse in the electrical line to the starter, free of charge. The recall began August 31, 2017. Owners may contact MBUSA customer service at 1-800-367-6372. MBUSA's number for this recall is 2017080002.

Engine And Engine Cooling:engine

Mercedes-Benz USA, LLC. (MBUSA) is recalling certain 2015-2017 C300 4Matic, C300, CLA250, CLA250 4Matic and CLA45 AMG vehicles, 2017 C300 4Matic Cabrio, C300 4Matic Coupe, C300 Cabrio, C300 Coupe, E300, E300 4Matic, E400 4Matic Wagon, E43 AMG 4Matic, GLA250, GLA250 4Matic and GLC300 4Matic Coupe vehicles and 2016 C350e and GLC300 vehicles and 2016-2017 C450 4Matic AMG Sport and GLC300 4Matic vehicles. In the event that the engine or transmission cannot turn over, the starting current limiter may overheat from the repeated attempts of the starter motor attempting to start the vehicle.

Consequence: If the starting current limiter overheats, the surrounding components can melt, increasing the risk of a fire.

Remedy: MBUSA will notify owners, and dealers will install an additional fuse in the electrical line to the starter, free of charge. The recall began August 31, 2017. Owners may contact MBUSA customer service at 1-800-367-6372. MBUSA's number for this recall is 2017080002.

16V087000 · Visibility:sun/moon Roof Assembly

Feb 16, 2016

Mercedes-Benz USA, LLC (MBUSA) is recalling certain model year 2016 C300 vehicles manufactured December 11, 2015, to December 23, 2015, C300 4Matic vehicles manufactured December 12, 2015, to December 29, 2015, and C450 AMG 4Matic vehicles manufactured December 12, 2015, to December 22, 2015. The affected vehicles may be equipped with a panoramic sunroof that may not be properly bonded, allowing the glass to detach and fall from the vehicle during operation.

Consequence & remedy

Consequence: If the panoramic glass detaches during vehicle operation, it can increase the risk of injury or crash.

Remedy: MBUSA will notify owners, and dealers will inspect the bonding of the rear sunroof glass panel, replacing it as necessary, free of charge. The recall began on April 12, 2016. Owners may contact MBUSA customer service at 1-800-367-6372.

Model-level recall history does not show whether a particular VIN is affected or has received a repair. Check a VIN with NHTSA ↗

NHTSA investigations

2

EA21002 · Desiccated Air Bag Inflator Rupture

Opened Sep 17, 2021 · No close date supplied

Status: open (inferred from source dates) · Air Bags:frontal:driver Side:inflator Module; Air Bags:frontal:passenger Side:inflator Module

From 2000 through 2017, Takata produced millions of air bag inflators using two types of phase-stabilized ammonium nitrate ("PSAN") propellant -- propellant 2004 and propellant 2004L. After prolonged exposure to high temperature cycles and humidity, inflators using propellant 2004 can degrade, causing the propellant to burn too quickly when ignited. The rapid burning can cause the inflator to rupture during deployment, potentially causing serious or even fatal injury to vehicle occupants. See 2016 Blomquist Report at www.nhtsa.gov/sites/nhtsa.gov/files/documents/expert_report-hrblomquist.pdf.Consequently, all frontal inflators using propellant 2004 that do not contain a "desiccant" (a substance that traps and holds moisture) in US vehicles are under recall. These "non-desiccated" inflators either have been or are required to be replaced.In some cases, the remedy part for these recalled inflators was, or will be, an inflator using either propellant 2004 or 2004L that does contain a desiccant. None of these "desiccated" remedy parts (which were installed in older model year vehicles) are currently under recall for a degradation concern. Certain subsets of desiccated PSAN inflators using propellant 2004 for use as original equipment, however, have been recalled for a degradation concern. All Takata inflators produced with propellant 2004L contain desiccant, and none of these desiccated inflators using propellant 2004L are under recall for a degradation concern. There have been no reported field ruptures in any non-recalled desiccated PSAN inflators.It is understood that desiccants fully saturate at some threshold, at which point any additional moisture will not be captured. This means the degradation process observed in non-desiccated inflators using propellant 2004 may also occur in non-recalled desiccated inflators using propellant 2004, assuming additional moisture enters the inflator and high temperature cycling occurs. Based on available information, desiccant saturation can occur within the first five years in the worst environments, and the time required for full saturation is affected by multiple factors. While no present safety risk has been identified, further work is needed to evaluate the future risk of non-recalled desiccated inflators using propellant 2004.Three entities -- Takata (now known as TK Global), the Independent Testing Coalition, and Exponent -- have been studying the long-term behavior of Takata desiccated PSAN inflators using propellant 2004L (as well as 2004) in the presence of moisture and temperature cycling. The research efforts, which include development of predictive modeling techniques and field sample analysis, are ongoing. To date, none of the researchers have identified field evidence showing that propellant 2004L is undergoing a degradation process that leads to aggressive deployment and potential rupture. However, the time in service of such inflators remains short compared to that of the inflators using propellant 2004. Further study is needed to assess the long-term safety of desiccated inflators using propellant 2004L.The Office of Defects Investigation is opening this investigation to examine whether a safety defect related to propellant degradation exists in non-recalled desiccated PSAN frontal inflators manufactured by Takata. This investigation will require extensive information on Takata production processes and surveys of inflators in the field. Lists of recall actions that may have used desiccated PSAN inflators as remedy parts, as well as the makes and models originally manufactured with them, is available with the downloadable version of this document (see nhtsa.gov/recalls?nhtsaId=EA21002 -- note this information is subject to change/revision as the investigation proceeds). This investigation does not supersede EA15-001, which remains open.

Additional source detail variants (2)

Air Bags:frontal:driver Side:inflator Module

From 2000 through 2017, Takata produced millions of air bag inflators using two types of phase-stabilized ammonium nitrate ("PSAN") propellant -- propellant 2004 and propellant 2004L. After prolonged exposure to high temperature cycles and humidity, inflators using propellant 2004 can degrade, causing the propellant to burn too quickly when ignited. The rapid burning can cause the inflator to rupture during deployment, potentially causing serious or even fatal injury to vehicle occupants. See 2016 Blomquist Report at www.nhtsa.gov/sites/nhtsa.gov/files/documents/expert_report-hrblomquist.pdf.Consequently, all frontal inflators using propellant 2004 that do not contain a "desiccant" (a substance that traps and holds moisture) in US vehicles are under recall. These "non-desiccated" inflators either have been or are required to be replaced.In some cases, the remedy part for these recalled inflators was, or will be, an inflator using either propellant 2004 or 2004L that does contain a desiccant. None of these "desiccated" remedy parts (which were installed in older model year vehicles) are currently under recall for a degradation concern. Certain subsets of desiccated PSAN inflators using propellant 2004 for use as original equipment, however, have been recalled for a degradation concern. All Takata inflators produced with propellant 2004L contain desiccant, and none of these desiccated inflators using propellant 2004L are under recall for a degradation concern. There have been no reported field ruptures in any non-recalled desiccated PSAN inflators.It is understood that desiccants fully saturate at some threshold, at which point any additional moisture will not be captured. This means the degradation process observed in non-desiccated inflators using propellant 2004 may also occur in non-recalled desiccated inflators using propellant 2004, assuming additional moisture enters the inflator and high temperature cycling occurs. Based on available information, desiccant saturation can occur within the first five years in the worst environments, and the time required for full saturation is affected by multiple factors. While no present safety risk has been identified, further work is needed to evaluate the future risk of non-recalled desiccated inflators using propellant 2004.Three entities -- Takata (now known as TK Global), the Independent Testing Coalition, and Exponent -- have been studying the long-term behavior of Takata desiccated PSAN inflators using propellant 2004L (as well as 2004) in the presence of moisture and temperature cycling. The research efforts, which include development of predictive modeling techniques and field sample analysis, are ongoing. To date, none of the researchers have identified field evidence showing that propellant 2004L is undergoing a degradation process that leads to aggressive deployment and potential rupture. However, the time in service of such inflators remains short compared to that of the inflators using propellant 2004. Further study is needed to assess the long-term safety of desiccated inflators using propellant 2004L.The Office of Defects Investigation is opening this investigation to examine whether a safety defect related to propellant degradation exists in non-recalled desiccated PSAN frontal inflators manufactured by Takata. This investigation will require extensive information on Takata production processes and surveys of inflators in the field. Lists of recall actions that may have used desiccated PSAN inflators as remedy parts, as well as the makes and models originally manufactured with them, is available with the downloadable version of this document (see nhtsa.gov/recalls?nhtsaId=EA21002 -- note this information is subject to change/revision as the investigation proceeds). This investigation does not supersede EA15-001, which remains open.

Air Bags:frontal:passenger Side:inflator Module

From 2000 through 2017, Takata produced millions of air bag inflators using two types of phase-stabilized ammonium nitrate ("PSAN") propellant -- propellant 2004 and propellant 2004L. After prolonged exposure to high temperature cycles and humidity, inflators using propellant 2004 can degrade, causing the propellant to burn too quickly when ignited. The rapid burning can cause the inflator to rupture during deployment, potentially causing serious or even fatal injury to vehicle occupants. See 2016 Blomquist Report at www.nhtsa.gov/sites/nhtsa.gov/files/documents/expert_report-hrblomquist.pdf.Consequently, all frontal inflators using propellant 2004 that do not contain a "desiccant" (a substance that traps and holds moisture) in US vehicles are under recall. These "non-desiccated" inflators either have been or are required to be replaced.In some cases, the remedy part for these recalled inflators was, or will be, an inflator using either propellant 2004 or 2004L that does contain a desiccant. None of these "desiccated" remedy parts (which were installed in older model year vehicles) are currently under recall for a degradation concern. Certain subsets of desiccated PSAN inflators using propellant 2004 for use as original equipment, however, have been recalled for a degradation concern. All Takata inflators produced with propellant 2004L contain desiccant, and none of these desiccated inflators using propellant 2004L are under recall for a degradation concern. There have been no reported field ruptures in any non-recalled desiccated PSAN inflators.It is understood that desiccants fully saturate at some threshold, at which point any additional moisture will not be captured. This means the degradation process observed in non-desiccated inflators using propellant 2004 may also occur in non-recalled desiccated inflators using propellant 2004, assuming additional moisture enters the inflator and high temperature cycling occurs. Based on available information, desiccant saturation can occur within the first five years in the worst environments, and the time required for full saturation is affected by multiple factors. While no present safety risk has been identified, further work is needed to evaluate the future risk of non-recalled desiccated inflators using propellant 2004.Three entities -- Takata (now known as TK Global), the Independent Testing Coalition, and Exponent -- have been studying the long-term behavior of Takata desiccated PSAN inflators using propellant 2004L (as well as 2004) in the presence of moisture and temperature cycling. The research efforts, which include development of predictive modeling techniques and field sample analysis, are ongoing. To date, none of the researchers have identified field evidence showing that propellant 2004L is undergoing a degradation process that leads to aggressive deployment and potential rupture. However, the time in service of such inflators remains short compared to that of the inflators using propellant 2004. Further study is needed to assess the long-term safety of desiccated inflators using propellant 2004L.The Office of Defects Investigation is opening this investigation to examine whether a safety defect related to propellant degradation exists in non-recalled desiccated PSAN frontal inflators manufactured by Takata. This investigation will require extensive information on Takata production processes and surveys of inflators in the field. Lists of recall actions that may have used desiccated PSAN inflators as remedy parts, as well as the makes and models originally manufactured with them, is available with the downloadable version of this document (see nhtsa.gov/recalls?nhtsaId=EA21002 -- note this information is subject to change/revision as the investigation proceeds). This investigation does not supersede EA15-001, which remains open.

PE21001 · Front Roof Panel Detachment

Opened Jan 8, 2021 · Closed Oct 14, 2021

Status: closed (inferred from source dates) · Structure:body:roof And Pillars

On January 8, 2021, after ongoing review with Mercedes Benz, the National Highway Traffic Safety Administration (NHTSA) Office of Defects Investigation (ODI) opened PE21-001 to assess allegations of front roof panel detachments while driving at highway speeds in certain 2015 Mercedes-Benz (Mercedes) C-Class vehicles.The subject front roof panel is a stationary panel composed of polycarbonate and is attached to the vehicle via adhesive at the time of manufacture. The panel is found on subject vehicles equipped with panoramic sunroofs. Over time, the subject panels may exhibit cosmetic degradation leading to replacement of the panel, a procedure which entails: removal of the old panel and adhesive, site preparation, and installation of a replacement panel with new adhesive.The consumer complaints that prompted the opening of PE21-001 all described detachments of front roof panels that had been replaced after the vehicle was put into service.Mercedes' internal investigation identified a broader scope of affected vehicles (2014-2020 CLA, GLA, C, S, GLC, and GLE class) and found the following potential service procedure- related causes of front roof panel detachments:- Improper surface pretreatments such as the use of the wrong primer or cleaner or scoring of the surface; or - Use of the incorrect adhesive.These conditions lead to a front roof panel bond that, even if sound at the time of repair, cannot maintain its strength over time and environmental exposure.Mercedes updated its service and parts ordering systems to reinforce the proper use of specified kits and procedures via webinars, shop foreman meetings, and explicit reference to the risks incurred by diverging from the repair procedures. Mercedes is also furnishing parts ordering assistance, and will hold dealerships accountable for improper repairs.ODI's analysis of the ten complaints it has received from the public (VOQ's) and MBUSA's complaint data submitted in response to the information request letter for PE21-001 identified a total of 57 non-duplicative reports alleging incidents in which the front roof panel detached from the vehicle while in motion. Included within the 57 reports are incidents where consumers state the panel detached ...and flew off into traffic.On March 19, 2021, Mercedes notified NHTSA that it would recall subject vehicles with front roof panels known to have been replaced after the original sale of the vehicle. In total, the recall (designated as Recall 21V197) covers 15,099 vehicles that were ever registered in the United States. Based on Recall 21V197 and the remedy implemented by Mercedes, further investigation does not appear to be warranted at this time.Accordingly, this investigation is closed.The ODI complaints cited above can be viewed at www.nhtsa.gov under the following ODI identification numbers: 11376425, 11352686, 11351629, 11349158, 11341541, 11337594, 11324100, 11311591, 11222127, 11404183